Draw plate



119% 1951 M. R. CLEMENT ET AL 2,578,229

DRAW PLATE Filed Jan. 27, 1948 4 Sheets-Sheet l 7 U U Ilvvs/vrofls: 27 23 MARceL CLEMENT AND DAN/EL E. GERMA/N Dec. 11, 1951 M. R. CLEMENT ET AL2,578,229

DRAW PLATE Filed Jan. 27, 1948 4 Sheets-Sheet 2 IN l/E/VTORS MARCEL RCLEMENT AND DAN/1. E GERMA/lv '7} be 1951 M. R. CLEMENT ET AL DRAW PLATE4 Sheets-Sheet 3 Filed Jan. 27, 1948 I/v VE/V NA Rea CLEMENT DAN 1. E W

Dec. 111, 1951 M. R. CLEMENT ETAL 2,578,229

DRAW PLATE Filed Jan. 27, 1948 4 Sheets She t e L IN VE/VTO/VS MARCELFF. CLEMENT AND DAN/El- E, GERMAl/V Patented Dec. 11,1951

OFFICE DRAW PLATE Marcel Ren Clement, Montreuil, and Daniel EmileGermain, Paris, France Application January 27, 1948, Serial No. 4,504 InFrance November 17, 1947 1 Claim. 1

Our invention refers to improvements in the draw plates for rods, bars,tubes and similar sections.

The object of the invention is to allow not only the drawing of piecesof uniform cross-section but also to effect the drawing in one singleoperation without involving any changing of machine parts, of suchpieces as rods, bars or tubes, of which the cross-sectional area maydiffer in any way throughout their length, whatever may be the shape,size and change in their crosssection.

The main point of our draw-plate, including improvements as set forth inthe invention, lies in the fact that it comprises a set of jaws of apolygonal shape that are arranged concentrically with the drawing axis,while leaving around the axis an opening through which may pass thepiece to be drawn and the jaws are placed next to each other, with eachside touching the adjacent jaw; these jaws are assembled together in asuitably shaped set up so that the cooperating sides may slide againsteach other and so that this motion may open up a passage way of varyingsection that may be adjusted to any particular cross-sectional area tocorrespond with the shape that it is desired to give the piece that isbeing drawn. Such an adjustment may be made at the start for pieces ofuniform cross-section, or it may be changed during the drawing processthrough a mechanical means of control in the case of pieces for whichthe cross-sectional area is to be altered as the drawing is carried on,so that the pieces may be drawn out in one operation while using thesame machine parts.

The invention takes in, also, certain auxiliary attachments, the use ofwhich will appear in the detailed description given later on.

The following specification to be read with reference to theaccompanying drawings submitted asan example deals with a method ofcarrying out the improvements as outlined above and will provide aclearer understanding of our invention. In the drawings:

Fig. 1 is a diagrammatic view showing in through section the shape andarrangement of the jaws assembled in their frame.

Fig. 2 shows a through section showing the shape of an individual jaw.

Fig. 3 shows a longitudinal section of the die through the drawing axis.

Fig. 4a is a sectional view of the die at right angles to the drawingaxis i. e. through the line (1-2) of Fig. 3.

Fig. 4b is an elevational front view of the die.

Fig. 5 is a perspective view of the expanding part of the die.

The die, according to the embodiment illustrated, includes a set ofjaws, eight for instance, shown in Fig. l at l-23-45Gl8 and their lengthis such as given for jaws No. 4 and 8 in Fig. 3 while their transversalsection assumes the shape of an isosceles triangle with one chamferedvertex, as will be seen at 9 in Fig. 2

These jaws are assembled concentrically with the drawing axis it andplaced side by side, so that two adjacent jaws are always in contactalong one of their sides, the jaw system being held within the innerline of the ring II which line is octogonal in shape, each jaw bearingthrough its chamfered base on one side of this octogon. Naturally, thenumber of sides of the inner straightline figure within the ring willcorrespond with the number of jaws. The jaws assembled in this wayinside the ring are shown by full lines in Fig. l and are so placed thatall their apices meet together at the centre point of the ring so thatthere is in this case no space left around the axis Ill. It is easy tofigure that if any movement is given to one of the jaws, say jaw 8 inthe direction of its base, that is of the arrow 0 and since one of thevertices of the isosceles triangle is chamfered, this particular jaw maymove in the direction of the arrow, with an accompanying movement of allthe other jaws that will slide against each other along theircooperating sides and along the sides of the polygon through theirchamfered base or side until the end 8 of the chamfered side of jaw 8for instance, meets the end I l of the next side of the polygon that isparallel to the chamfer. The assembled group of jaws will then assume aposition such as that shown by dotted lines in Fig. l, where they leavean opening around the axis l0 through which the piece to be drawn maypass. When the jaws are arranged as shown in dotted lines, the openingis at its widest and the jaws can move no further in the directionreferred to.

It should be observed that the adjacent sides of the 45 angle at theapex of each triangle forming a jaw fit accurately against the sides ofthe adjacent triangle, the right hand sides (Fig. 2) being for instanceconvex while the left hand sides are correspondingly concave, for thepurpose of constituting a closely packed grouping of the triangles. Thefitting together of these triangles or jaws is carried to the finestdegree of accuracy and these triangles are made up of a suitablematerial that has been subjected to the necessary treatment.

The size of the opening will depend on the amount of movement impartedto the jaws. This size of the opening will be adjusted to correspond tothe cross-sectional area to be given to the piece to be drawn.

In the case of a piece in the shape of a rod, bar, tube or the like thathas to be drawn with a uniform cross-section throughout its length, therequired adjustment is made as the first step of operation and theopening for the particular piece considered remains the same while thedrawing work is being carried out.

Furthermore, the ring H is set in the frame of the die in associationwith suitable mechanical means whereby the movement of the jaws insidethe ring may be controlled readily from the outside of the ring at anytime so that the opening may be made smaller or wider during the travelof the piece through the die, and consequently the cross-sectional areaof the piece being drawn may be altered at will.

The arrangements that come within the scope of the invention and allowthe drawing to be controlled in this manner are shown in Figures 3 and4.

The jaws are held in the ring II by two cheek plates I2, l3 attached tothe latter by screws of which two, 14 and I5, are shown in Figure 3. Thering ll itself is attached by screws to a bearing plate It that forms aportion of the frame of the die. It is surrounded by a wheel I? withouter spiral teeth and bears on two opposite cylindrical segments of theinner periphery of this wheel, as will be, seen at [8, l9 in Figuresla-4b with these two cylindrical segments connected by cut-away segments20, 2| the curvature of which widens out from the periphery of the ringstarting from their common points of contact to either side of segment19.

The wheel with spiral teeth H engages with a worm gearing 22 carried onthe plate 16 by suitable fittings 23 (Figure 3) The worm gearing 22carries at one end a replaceable grooved drum 24 that may be turned bymeans of a wire or cable 25 controlled by any suitable means.

The ring H has a sloping hole 26 drilled through it that goes alsothrough the lower jaw 4. In this hole may move to either side of the jaw3 lying between 2 and 4, two push-rods 21, 28 that bear through one oftheir ends on opposite surfaces of jaw 3, with these surfaces containingfiat parts for this purpose. The other ends of these push-rods bear onthe surfaces of the grooved segments 29, 2| of the inner periphery ofwheel ll.

It will be clear that if the wheel I! is turned through any small angleby means of the control drum 24, the grooved segments 20, 2| will act asa cam on either one or the other end of a push rod and these push-rodswill then move the jaw 3 in one direction or the other, thus impartingan equivalent motion to all the other jaws as explained above. It willbe obvious that only one of the push rods comes into action depending onthe direction of rotation of the wheel, with the other push-rod onlyacting to keep the jaw 3 in its right position in the general set up.

The working of this device is self explanatory. Attention may be drawnfurther to the fact that scale divisions are marked on the groovedsegments as shown in Fig. 4b. They agree with the size of thecross-sectional area of the axial opening through which the pieces haveto pass the chamfered angle of the jaws.

and thus allow the adjustment of this opening at will and with a highdegree of exactitude. It will be noted that both ends of the twopushrods bear on corresponding scale divisions of the two groovedsegments whatever the position of the wheel may be.

It will be easily realised that the opening, through which the pieces tobe drawn have to pass may be altered by acting on the drum 24 and thismay take place just as well before the drawing starts as durin theactual drawing operation. Consequently adjustment may be made fordrawing a piece with a uniform cross-section throughout its entirelength, but this cross-sectional area may be changed as desired duringthe drawing procedure, without any pause in the operation and withouthaving to replace any of the jaws or any other part of the machine, sothat a piece may be obtained with a varying cross-section over itslength, whatever the size and shape of the various sections drawn.

It will be an easy matter therefore, with a die according to theinvention on the one hand to draw to a section that has been adjustedaccurately beforehand, such items as rods, bars and tubes shaped as aprism, pyramid or cone throughout their length with a regular orirregular uniform cross-sectional area and on the other hand, to drawpieces that are similar in their longitudinal contour and of variablepolygonal cross section over the length of the piece, while this changein shape may be in turn an increase and decrease in cross-sectionalarea. Special pieces may thus be drawn consisting of one single piecemade up of several pyramid or cone frusturns of varying slopes andlengths.

The degree of accuracy to be got is of the order of mm. There is a widerange of sizes that may be given to the area of the opening throughwhich the pieces have to pass, in practice, the range of this openingmay go from 0 mm. to 14 mm. reckoned between the opposite fiat surfacesof the polygon that this opening makes. These numbers are only given asa guide and may be higher if desired.

In the particular example taken, a, selection has been made of 8 jawsbut of course this number could vary; however as a working principle thelowest limit of jaws is three to give satisfactory operation. In thecase of three jaws, the inside contour of the ring would take the shapeof a triangle.

The maximum size -of the opening depends mainly on the size of thebevelled edge made by In fact, the greater the remaining length on thechamfered side, the greater is the movement that this side may make onthe corresponding inner level surface of the ring. However, the bevellededge must not go beyond a certain range in order to ensure that the jawsare held snugly in position.

It is advisahleto use mechanical means for controlling the drum 25. Whenit comes to pieces of uniform cross section throughout their length, itis better not to use a mechanical control and to employ instead a devicefor hand adjustment that allows the jaws to be brought into an unvaryingpredetermined position.

The invention, of course, is not tied down to the arrangements as setout above; on the other hand it takes in all modifications working onthe same principle, more particularly in those cases where the polygonalsection to be got would not be that of a regular polygon. I

The invention covers the novel articles of manufacture formed byarticles obtained with dies constructed on the lines of the invention.

What we claim is:

A draw plate for rods, bars, tubes and the like adapted to provideconstant and varying cross sections for said drawn members, comprising aseries of interlocked jaws having a substantially triangular crosssection and assembled about a drawing axis, in slidin relationship withreference to one another, a ring surrounding same and bounded inwardlyby a polygonal surface the number of sides of which corresponds with thenumber of the triangular jaws and the length of said sides being equalto that of the bases of the corresponding triangular jaws, thetriangular jaws having the outer edge facing a given diretion of angularmovement bevelled oil for allowing a relative movement of the jaw alongthe corresponding polygonal surface side, the ring being provided withtwo alined elemental transversal openings parallel with, in the vicinityof and on the inside of one of the sides of its inner transversepolygonal surface, the triangular jaws adjacent to the jaw sliding oversaid sides of the polygonal surface having a recess wide enough toalways register with the alined ring openings, the general angularshifting of the jaws round the drawing axis corresponding to a slidingof the jaws with reference to one another and along the sides of thepolygonal surface providing for a gradual modification of the innerpolygonal opening defined by the non bevelled lateral surfaces of thetriangular jaw, a helical wheel provided with the two longitudinal boredrecesses arranged symmetrically with reference to an axial plane ofsymmetry and the depth of which increases progressively from one end tothe other, means for securing rigidly inside said wheel the ring, theouter surface of which fits exactly the non recessed inner surface ofthe wheel, a worm controlling the rotation of the wheel, a two-partpusher rod the two parts of which bear respectively against the wall ofthe corresponding recess in the wheel, pass through the alined openingsin the ring and through the recess in the corresponding triangular jawsand engage cooperating surfaces on the jaw separating the recessed jaws.

MARCEL RENE CLEMENT.

DANIEL EMILE GERMAIN.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 629,747 Kuttler July 25, 1899686,365 Thackray Nov. 12, 1901 871,654 Woodhead Nov. 19, 1907 1,922,770Kornbrath Aug. 15, 1933

